1. Field
The present invention generally relates to nebulizers and, in particular, to the breathing devices used with a nebulizer dispenser.
2. Description of the Related Art
Medications for certain respiratory conditions, such as asthma and chronic obstructive pulmonary disease (COPD), are often administered as an inhaled aerosol to improve delivery of the medication to the lungs. A nebulizer, also referred to as a “nebuliser,” is a medical device which uses mechanical energy to transform a liquid medication into an aerosol. A nebulizer may use compressed gas forced through a nozzle to break up the liquid medication into tiny globules or may use ultrasonic or vibrating-mesh mechanisms to mechanically generate the tiny globules of liquid medication, thereby forming an aerosol mist.
Nebulizers are available in various sizes, including tabletop units that are plugged into an electrical outlet, such as shown in FIG. 1. The aerosol mist is delivered to the patient through a breathing element such as a mask, a nasal piece, or a mouthpiece that fits into the mouth.
Conventional designs for nebulizer dispensers produce a continuous flow of the aerosol mist irrespective of whether the patient is inhaling, exhaling, or not breathing on the device at all. One problem with conventional designs is that the aerosolized medication is only delivered to the patient while the patient is inhaling through the breathing device, with the aerosol mist that is generated while the patient is exhaling or not breathing through the device being lost to the ambient atmosphere.